J-20 can supercruise and is more stealthy than F-35
1. In a much earlier post, I quoted a J-20 Chinese test pilot who confirmed the J-20 can supercruise. F-35 cannot.
2. J-20 has a clean design like the F-22. I have already mentioned the two flaws in the J-20 design that makes it currently inferior to the F-22 (e.g. "some curvature of the sides" that need to be re-worked and glaring round engine nozzles). However, the F-35 is far more flawed with its compromised design of "‘hideous lumps, bumps, humps and warts’ [that] have appeared on the JSF to disrupt the shaping imperative."
3. Australia Air Power "Physical Optics simulation across nine radio-frequency bands" has shown the J-20 is optimized for stealth. In contrast, the F-35 design is mostly meant to defeat radars in two bands: "to best defeat radars operating in the X and upper S band."
In conclusion, aside from avionics, the J-20 Mighty Dragon is superior to the F-35 in both supercruise ability and stealth across all "nine radio-frequency bands."
----------
"In spite of being smaller than the F-22, the F-35 has a larger radar cross section. It is said to be roughly equal to a metal golf ball rather than the F-22's metal marble.[126] The F-22 was designed to be difficult to detect by all types of radars and from all directions.[127]
The F-35 on the other hand manifests its lowest radar signature from the frontal aspect because of compromises in design. Its surfaces are shaped to best defeat radars operating in the X and upper S band, which are typically found in fighters, surface-to-air missiles and their tracking radars, although the aircraft would be easier to detect using other radar frequencies.[127] Because the shape of the aircraft is so important to its radar cross section, special care must be taken to maintain the "outer mold line" during production.[128] Ground crews require Repair Verification Radar (RVR) test sets in order to verify the RCS of the aircraft after performing repairs, which was not a concern for previous generations of non-stealth fighters.[129][130]"
F-35 with "‘hideous lumps, bumps, humps and warts’ [that] have appeared on the JSF to disrupt the shaping imperative."
----------
J-20 Mighty Dragon has smooth and flat underside.
"
This study has therefore established through Physical Optics simulation across nine radio-frequency bands, that no fundamental obstacles exist in the shaping design of the J-20 prototype precluding its development into a genuine Very Low Observable design.
Above: L-band RCS, below X-band RCS head on, both in PCSR format (M.J. Pelosi).
Engineers and Scientists who work in ‘stealth’ (AKA ‘Low Observable’) designs have a way for explaining it to lay people: ‘Stealth’ is achieved by Shaping, Shaping, Shaping and Materials (Denys Overholser).
The F-22A is clearly well shaped for low observability above about 500 MHz, and from all important aspects.
The J-20 has observed the ‘Shaping, Shaping, Shaping’ imperative, except for the axisymmetric nozzles, and some curvature of the sides that smears a strong, but very narrow specular return into something of a more observable fan.
The X-35 mostly observed the ‘Shaping, Shaping, Shaping’ rule, but since then, to quote a colleague, ‘hideous lumps, bumps, humps and warts’ have appeared on the JSF to disrupt the shaping imperative, forcing excessive reliance on materials, which are at the rear-end of the path to ‘Low Observability’.
While discussing ‘rear-ends’, both the F-35 and the J-20 have large signature contributions from their jet nozzles. However, the difference is much like the proverbial ‘Ham Omelette’: the F-35 Pig is committed, but the J-20 Chicken is a participant.
If the Chinese decide that rear sector Low Observability is tactically and strategically important, they are at the design stage where they can copy the F-22A nozzle design for the production configuration of the J-20."
[Note: Thank you to HouShanghai for the J-20 underside picture and Stereospace for the F-35 underside picture.]
